Though if this escalates and EC approves it, whilst FTC now looks like a liar, it may be enough to sway CMA to the other direction and not align with FTC...There's a lot of Politics at play here.
If Microsoft wants to extend things long enough, I wonder how many appeal chances they get against CMA? Could they keep appealing CMA and having it thrown back to CAT then thrown back to CMA whilst fighting a court battle against FTC, beat FTC and then leave CMA all on their own.
I'd guess that would depend on how long Microsoft is willing to drag this out.